We are trying to determine by genetic and biochemical methods the interactions between different proteins in the replication and recombination complexes of phage T4. The gene 32 protein is a key element in these interactions and we will continue our studies to recognize such interactions in vivo by analysing mutation-specific suppressors. In addition we shall try to isolate the corresponding mutant proteins and determine their interaction potential and function in vitro. We will also collaborate with Dr. Robert Marsh at the University of Texas in Dallas to determine by restriction enzyme fragment analysis whether the first round to T4 DNA replication starts from one or from several origins. In addition, in collaboration with investigators at the Max-Planck-Institute fur Zuchtungsforschung in Cologne, Germany, we will study uptake and fate of DNA added to plant protoplasts. BIOGRAPHIC REFERENCES: Mosig, G. and Bock, S. Gene 32 Protein of Bacteriophage T4 Moderates the Activities of the T4 Gene 46/47-Controlled Nuclease and of the Escherichia coli RecBC Nuclease In Vivo, Journal of Virology, 17, 756-761 (1976). Mosig, G. Linkage Map and Genes of Bacteriophage T4, Handbook of Biochemistry and Molecular Biology, 3rd edition, pp. 664-676 (1976).